Team time zones

Build the roster once. Search a city for each person, correct the name, and set the hours they actually work rather than the hours in their contract. Someone who starts at 07:30 to be home for the school run has a different overlap than the default nine to five, and the bar is only as useful as the hours you put in it.

1. Read every bar against the ruler at the top, which is your own clock. A band that starts three columns to the left of yours means that person is three hours ahead of your morning.
2. Look at the bottom band before you book anything. It marks the minutes when every person on the roster is inside their own working day.
3. If the bottom band is empty, say so out loud instead of picking a time and hoping. Somebody is going to take that call outside their day, and it should be a decision rather than an accident.
4. Press Copy team link and paste it in the channel. Whoever opens it sees the same roster on their own clock, which is usually the fastest way to end a thread about what time works.

Why the bars move on their own

Offsets are computed from the real time zone rules in your browser, not from a fixed number of hours. When the United States changes clocks before Europe does, the bands shift for those weeks and the overlap changes with them. That gap is the single most common cause of a missed call in March and October, and the view shows it instead of hiding it.

Picking a time when nothing overlaps

Teams spread across more than about nine hours of longitude often have no shared working hour at all. The usual answers are to rotate which zone takes the awkward slot week by week, to keep one short call and move everything else to writing, or to accept a standing thirty minute overlap at the edge of two days and protect it. All three work. Pretending an overlap exists does not.

The strip covers the 24 hours from your own local midnight, and the shared band comes from sampling that span in five-minute steps. That is 288 samples, each kept only if every person on the roster is inside their own working hours at that moment, and the runs of kept samples are what gets drawn. The figure beside Everyone free is those minutes in hours to one decimal place, so an overlap of 2h 50m reads 2.8h.

The three rows the page starts with

The roster opens with three people on a nine to five: you in Lisbon, Mira in Berlin and Ana in New York. Read on a Lisbon clock, Berlin's band covers 08:00 to 16:00 and New York's covers 14:00 to 22:00, so the only stretch all three share is 14:00 to 16:00 and the label reads 2h today.

Now watch the same roster in late March. The United States moves its clocks on the second Sunday of March and the European Union on the last Sunday, a gap of two or three weeks depending on where those Sundays fall. Through it New York sits an hour closer to Lisbon, its band slides to 13:00 to 21:00, and the shared band grows to 13:00 to 16:00: three hours rather than two. The autumn version never varies, since the last Sunday of October and the first Sunday of November are always consecutive Sundays.

Rows that quietly empty the band

A row whose start and end times are identical, or whose times the browser cannot read, produces no band and says so in place of one. It still counts towards the shared band, so a single blank row leaves the bottom strip empty while the rows above it look fine. If the band disappears after you added somebody, check their hours before you believe it.